A sewer cleaning vehicle of the kind mentioned above is known from DE 195 38 846 A1. The conveying screw provided in the dirt removal container is arranged in this known arrangement in a stationary manner in the region of the container bottom. Reliable clearance of the dirt removal container only occurs when the container filling automatically slips downwardly to the conveying screw operating in the region of the container bottom. Experience has shown that this is often not the case because the material which forms the filling of the dirt removal container and consists of sedimented mineral dirt residues forms lumps and bridges. There is a likelihood in the known arrangement that the conveying screw arranged in the region of the container bottom runs out of material and subsequently runs empty, so that the material not situated in the direct area of action of the conveying screw is not removed. The discharge screw assembly arranged downstream of the conveying screw is arranged in extension of the conveying screw and is therefore only reliably supplied with material as long as the conveying screw is in alignment therewith, which exacerbates the aforementioned disadvantage even further. The known arrangement has therefore proven itself to be inadequately reliable and therefore often requires laborious manual intervention.
An apparatus for unloading ships is known from DE 222 585 A. The apparatus includes a conveying screw which extends in a longitudinal direction of the cargo hold and which is capable of oscillating about an axis parallel to the screw axis for the purpose of better covering the entire cargo hold. The cargo of the ship, however, is dry bulk material. Furthermore, the removal of the cargo occurs in an upward direction.